Just
before the eclipse1st
contact
When the moon begins to cover the sun
Dark Skies: Light levels fall gradually at first, accelerating
later. For about ten minutes before totality the skies darken considerably
and temperatures may drop as if before a storm.

Changing Colors: As the eclipse progresses, you may see the
sky change color and shadows sharpen.

Crescents:
Watch hundreds of crescent shaped images of the Sun, created by
tiny gaps between leaves in the trees, playing on the ground.

Animal Behavior: As darkness falls, observe how different
species behave. Birds may roost, other animals may act as they would
at dusk and flowers may close.
Advancing Wall of Shadow: Watch a wall of shadow advance towards
you as totality approaches from the western sky.
Shadow Bands: Just before totality it sometimes looks as though
the earth moves as sensational shadow band. Parallel strips of light
and dark move rapidly across the ground
Bailey's Beads: A number of brighter points, like glass beads
are visible just before totality.
Diamond Ring: A dramatic effect like a shining brilliant diamond
set in a shining ring appears just before the eclipse.

Planets, Stars and Comets: Bright stars and some planets
like Venus, Mars and Jupiter become visible and remain visible during
totality.

At
the time of totality2nd
contact
Totality, When the moon completely covers the sun

Chromosphere:
The incandescent gas surrounding the sun can be seen as a pinkish
ring around the edge of the moon's disc.

Corona:
The solar corona is visible to the naked eye only during a total
eclipse. Pearly-white streamers radiate outwards and close observers
may see how the corona resembles a finely detailed engraving.

Period
of totality: The period of totality varies from place to place
and is usually lasts generally a few minutes to a maximum of seven
and a half minutes.

Just
after the total eclipse3rd
contact
the moment when the sun reappears from behind the moon.Diamond
Ring: The diamond ring effect again appears just after the eclipse.
Bailey's Beads: These bright spots become visible again.

Shadow Bands: These parallel strips of light and shadow similar
to those seen immediately before totality may be observed.